The present invention concerns a landing stage, in particular for offshore wind power installations.
Offshore wind power installations usually require a landing stage or landing pier so that craft, in particular ships, can guarantee supply and transportation services. In the case of small offshore installations, these are usually simple jetties with possible ways of making boats fast. In the case of larger offshore installations at which larger supply ships land, the landing installations are of a more expensive and complicated structure and have for example supply intermediate storage facilities such as fuel tanks and loading equipment such as cranes.
Helicopters, because of their lower service load capacity, are usually employed for the rapid transportation of personnel.
If, because of high wind speeds and a heavy sea, it is difficult for ships to land, to the point of being impossible, then helicopters temporarily represent the only supply and transportation option. Many offshore installations which do not have any landing area for helicopters, under such weather conditions, can then be supplied with a helicopter only in such a way that the helicopter which has flown to the installation remains in the air and supply or inspection is effected for example by means of a cable winch on the helicopter. Maneuvers of that kind are difficult and dangerous.
Offshore wind parks comprising a plurality of individual wind power installations which are disposed in the sea but also other, for example small, individual offshore installations, by virtue of their construction, afford scarcely any possible way of providing a landing area for helicopters on them. In addition, in the case of wind power installations, the danger to the helicopter as it flies towards the installation, due to the rotating rotor blades of the wind power installation, represents an addition serious problem.
The separate arrangement of the mooring location or berth for ships on the foundation legs and of the landing area for the helicopter at a higher position on the drilling rig, as is known from offshore drilling rigs, is essentially out of the question, because of the rotor being arranged at that location in the case of wind power installations, and, under the constricted situation in terms of space on offshore installations, because of separately required logistics and the respective space required for same, results in a disadvantageous waste of building space.
The object of the present invention is to provide a landing stage for ships and for helicopters, which while being of a simple structure can be used on offshore and shore installations.
That object is attained by a landing stage having the features set forth in claim 1. Advantageous configurations of the invention are set out in the appendant claims.
In accordance with the invention a landing stage has a mooring location or berth for ships and a landing area for helicopters. The landing stage is disposed in particular on offshore wind power installations, but also on installations which are erected on a bank or shore. In accordance with the invention in that case there is a common route link from the mooring location and the landing area to the installation. In that way, in accordance with the invention, logistical devices can be set up in such a way that they can be used jointly for the mooring location and the landing area. These are for example buildings in which landed people can (initially) seek protection, materials which have been landed or which are ready for collection can be held in intermediate store, but also fuel stores which are arranged together as well as navigational aids which can include signal navigation lights, radio direction-finding transmitters, but also pilot rooms with radar surveillance. Because in particular offshore installations of any kind are substantially basically highly restricted in terms of their space aspects, a concentration in accordance with the invention of logistically relevant locations (transport interface for ships and helicopters from the installation to the outside world) is extremely advantageous. The common landing stage, preferably with the jointly usable logistical devices, advantageously concentrates in accordance with the invention transport from the landing stage by way of the common route link to the installation where then further distribution from the common route link can be effected in any desired manner in a logistically simply plannable fashion.
The landing stage according to the invention is preferably mounted to an offshore wind power installation whose generator is driven by a rotor which rotates at the tip (pod) of a pylon about a horizontal axis. In that case the landing area for helicopters, in order to guarantee safe take-offs and landings, is remote from the pylon preferably by at least a third of the length of a rotor blade.
Preferably the landing stage according to the invention has independent foundations in the sea, that is to say the mooring location and the landing area are supported on a foundation on the seabed or supported floatingly on the surface of the water, more specifically individually or separately from each other and in then any combination of the kind of support.
Preferably the landing stage is disposed laterally of the installation at the prevailing lee side of the installation. In that way the landing stage is advantageously disposed in the region of the installation which is sheltered from the wind, so that both wind and also sea swell break against the installation and only act with an alleviated force on the landing stage.
In accordance with the invention, that effect is further enhanced if the landing stage is preferably mounted rotatably about the offshore installation and is thus always oriented into the lee side of the installation by the afflux flow of wind. Particularly suitable for this embodiment of the invention is the floating foundation for the landing stage, which for example can be in the form of a pontoon of large area, which can be connected by way of a bridge for example to the base region of an offshore wind power installation and then is supported there for example by means of a ring sleeve or a rotor member on the periphery of the base. When applied to wind power installations, that design configuration has an additional substantial advantage: the greatly projecting rotating rotor blades of the generator propeller represent a major danger to a helicopter flying towards the installation. If now however in accordance with the invention the landing stage is oriented by the wind into the lee side of the wind power installation, the air space above the landing stage is at any event outside the rotational range of the generator propeller for the latter is in accordance with its function oriented transversely with respect to the lee side against the windxe2x80x94in other words: in relation to the wind direction, the plane of rotary movement of the generator propeller is then perpendicularly markedly upstream of the air space above the landing stage and does not cut through the air space. Furthermore, the helicopter can advantageously come in to land on the landing area against the wind without being impeded by the installation.
The embodiment of the landing stage according to the invention with the floating foundation also has the advantage that in respect of its height it follows the movement of the tides, which is of substantial advantage for the mooring location of the ships.
The landing stage according to the invention is preferably a structure made up of any combination of steel framework, plates, concrete and/or wood with suitable corrosion protection in relation to sea water and other environmental influences.